There has been known a mesa-type semiconductor element having the structure where a pn junction is exposed on an outer peripheral tapered region which surrounds a mesa region (see patent literatures 1 and 2, for example). FIG. 18 is a view provided for explaining a conventional mesa-type semiconductor element 900.
The conventional mesa-type semiconductor element 900 includes, as shown in FIG. 18, a mesa-type semiconductor base body 908 having a pn junction exposure portion C in an outer peripheral tapered region B surrounding a mesa region A, and a glass layer 924 which covers at least the outer peripheral tapered region B. The glass layer 924 is a glass layer for passivation made of “a glass material containing lead silicate as a main component”. In FIG. 18, symbol 910 indicates an n−-type semiconductor layer, symbol 912 indicates a p−-type semiconductor layer, symbol 914 indicates an n+-type semiconductor layer, symbol 916a indicates a silicon oxide film, symbol 934 indicates an anode electrode layer, and symbol 936 indicates a cathode electrode layer.